The thinking on how to answer this critical question is changing

Experts are starting to rethink how much stock people should hold in retirement.

In general, the new thinking goes, people should be more heavily invested in equities than is suggested by some traditional rules of thumb, such as subtracting one's age from 100 to determine a portfolio's stock allocation. One new, and controversial, theory even goes so far as to suggest that stock exposure should increase the further one moves into...